Casing for impellers of rotary blowers.



T. W. GREEN. CASING FOR IMPELLERS OF ROTARY BLOWERS.

APPLICATION FILED MAY 10. 1912.

, Patnted D60. 10, 1912.

) 2 SHEETS-SHEET 1.

jmwmao FM: 3 i 15 4 INVENTOR A TTORNE Y T. W. GREEN. CASING FORIMPELLERS'OP ROTARY BLOWEBS.

APPLIGATION FILED MAY 10, 1912.

Patented Dec. 10, 1912.

2 SHEETS-SHEET 2.

INVENTOR A TTORNE Y of Philadelphia, Pennsylvania,

To on whom ferred form of my casing ap 1 Fig.1, with a THOKAS W. GREEN,

I casino ron rrrmnnnnrnn, PENNSYLVANIA.

ELLE-BS OF ROTARY BLOWEBS.

concern: Be 1t known that I, Tnoms W. fGnEnN, a citizen of the UnitedStates,and a resident vented a certain new and the Impellers of RotaryBlowers, the following is a specification.

The purpose of my invention is to save in weight and thickness of metaleconomizing of which both in this way and in the cost of machin-- ingthe casings for impellers such as are used in blowers, 'exhausters andpumps.

A further purpose of my invention is to substitute rolled sheet or platematerial for cast iron in the curved outer casing parts of rotaryblowers, exhausters or pumps.

A further purpose of my invention is to enable the manufacturer tofinish the outer curved surfaces of the cast ends or heads of blowers,etc, in a lathe, boring mill or other A further purpose of my inclosewithin an extension of the casing the gearin which keeps the impellersin step and drives one impeller.

Further purposes of myinven'tion will appear from the specification andthe claims.

I have preferred to illustratemy invention by one form thereof which Ihave determined to be light, inexpensiveand efficient, and which wellillustrates the principles thereof.

Figure 1 is. a top planview of the prelied to a blower. Fig. 2 is avertical section 0 the structure of portion of the casing removed. Fig.3 is an elevation of the structure shown in Figs. 1 and 2, viewed fromthe pulley end but with the pulley removed. Fig. 4; is a section of theform shown in Fig. 1 taken upon lines H thereof.

;-have heretofore been cast The manufacture of impeller casings,particularly for the larger size blowers that weigh several tons hasinvolved much diiliculty and a great expense. These casings and a largepercentage of them has been spoiled in the molding, even when conditionsfavorable. Frequently the rough castings contain blow holes and otherimperfections that are not discovered until a great amount of time andlabor has been expended thereon. The great size of the flasks requiredand the difiicult-y in holding the parts in place during the castingoperation, combine to make the foundry work very expensive and trouble-Speeification of Letters Patent. A Application filed Kay 10, 1912.scream. 90,309.

have inuseful Casing for 'not always register accurately.

ave been the mostsome. The of the flask as well as.

the uneven cooling require excessive allowance of material for machininresulting in a waste of metal which is psi for at foundry prices,including labor, and is sold as Patented Dee.10,1912.

scrap. The finished cast casing is many times uneven in thickness,excessively heavy and bulky and cannot be divided to the best advantagebecause of the machining required. During the machining and setting up,the casings are frequently strained with the result-that the'impellersand casings do My invention is intended to overcome'all of the'difiiculties stated and to produce a lighter, stronger and cheapercasing, with which the impellers can more easily be-made to register Myinvention is shown as applied to a rotary blower of the type having twoim eller members, the outer end of the blade 0 each forming a seal withthe waist of'the other. Evidently it is applicable also to other formsof blowers and pumps. In the double impeller pumps and blowers thecentral section, within which the inlet and outlet air connections aremade, is preferably straight from side to side in the middle section, asindicated at -1 and 2 of the preferably cast central section 3 which Ihave shown as secured to the base in any suitable manner. Upon eitherside of this central section, with the two-impeller construction shown,is located a semi-cylindrical casing or shell, shown at 5 and 6respectively, corresponding closely in shape to the art of the extremeouter portion of the b ade of the impeller upon that side of the bloweror pump. This outer portion of the impeller, in'the form shown, isprovided with the packing 7. At the ends the semi-cylindrical sidecasing parts are :closed by semi-circular heads 9, 9' and 10,

10'. With other multi-blade constructions, the portion of thecircumference represented in the semi cylinder and the semi-circlerespectively, will differ in accordance with the construction of themachine and will not always represent as much as half of a circle. Theapplication of my invention to these forms will sufficiently trationhere shown.

It has been customary to cast the entire outer casing or shell, dividingin various ways as'may he required for the necessary coring and toprovide for'the accessibility of the impeller parts from the endthereof.

appear from the illusplate, side walls; and

: head greatly savin is a I g p .at 17, 1s and is 22 and 23 are shown.

I ings for the shafts 27 and 28 and are held.

vided with partition circular ends and 31 for the central end sec-1,004,776 and here intended to represent conventional impellers.

sin

These cast heavy. 1 v

I have found that the casing may be separated vertically parallel to theimpeller axes to advantage, along the edges 11, 12', between the centralstraig t portion and the semicylindrical side parts; thatthesemi-circular ends upon the same side may be cast separately and coveredwith semi-c lindrical that the en may be trued-up along'the-faccsthereof which ongage with the central straight part and fastened each tothe other so as to be finished upon a boring bar or lathe as onecircular in the'expenseof finhave been excessively For-convenience, 'Isplit the intermediate portion 3 up into four two end plates 13, 14 anthe top and bottom frames 15 and'16. Each of. the central end platespreferabl provides bearing for one half of an impe er shaft'upon eachside as stiffened at these bearings horizontally by web 19..andlverti'call flanges 20 and 21 stiffened transversel 20' and 21'. Attheto and bottom, flanges he flanges-2Q, 21, 22 and 23 are effective tojoin the parts to mating flanges upon the se '-circular end plates andthe top and bottom central sections by any suitable fastenings, shown at24. The caps 25, 26 coiiperate upon each end-with the bearing members17, 18 to complete the bear- 1n place by any suitable means, such as thebolts 29 shown. The ends 9 and 10, as well as the central section 13 atthis end, are pro- 'walls 30 for the semitlons, coiiperating to closethe interior of the casing at this pomt a inst each other and theimpeller shafts. utside of this partition, however, an elong housing isformed by slde walls 32, 33 and end walls 34, 35 parallel vwith thepartitions 30 and 31 to inclose and protect the gears 36 by which theimpeller shafts are main} tained in uniform rotation and both areimelled by pulley 37. The housing thus ibrmed add tionally stiflens thisend of the impeller casing t'owhich the driving pulley is connected andupon which the strain is correspondingly increased.

I have illustrated two impellers 38 and 39 of a type-claimed by me inmyPatent N o.

The portlons of the from the other, repeachimpeller blade outside of theintermediate casing sections, is'in substantial contact with thesemi-cylindricalside portions 5 and 6' to whose construction m mvention.as' here illustrated partly appl1es., The semi-circular heads 9 and 9'and 10 and 10 after being travel of each farthest arts comprising thefaced on their straight edge portions are clamped together and turned inany suitable manner, as upon a boring mill, to turn off thecircumferences 40, 40 41 of the other set at a preferably turning offthe all of the semi-circular end operation as the simplest way ofinsuring the same diameter for each. They may be'bored 'for the .shaftat the same setting. The semiciroular end pieces may then beconveniently clamped respective ends after these flanges have been facedto the desired distance between their outer faces. I then bend metal,suit-ably flanged at their side edges as at 42, temporarily using aninternal form between the ends where the separation of the end piecesmakes this desirable, and rivetor otherwise fastening :the plate metalto the flanges 43 and 44 at any suitable inter- .vals. The flanged edges42 are preferably tom intermediate sections. Any desired stiffening'orexternal suppor may be givento j the semi-cylindrical sheets of metalthus formed by external re-inforcing strips or sections 46 here shown asof T section and ;spaced at any suitable intervals. The sheet metal mayordinarily be secured to the sealmg contact, without the use of high, orwhere for any other reason leakage is feared or found to exist any kindof packated gear c'over' or 'lng may be inserted to improve or securethe joint or the edge isame purpose. In the assemblage of my device, thecentral frame parts can be erected and the impellers lifted to placebefore the semi-cylindrical side pieces are fitted on and before orfafter the top member 15 is placed. These gthe impellers may be removedby removal of the one semi-cylindrical side piece with its end piecesattached and entire lateral withjdrawal of the impeller until it willswing clear of the to piece 15, when it may be lifted outeit erupwardly. or axially. b 1ere the space does not permit this, it can e 1the half bearing of the middle section and t p lifting of the impeller.

'tional weight and cost of metal otherwise the semi-cylindrical surfacesreplaced by plate metal as well as the additional metal which would haveto be cast these castings and subsequen boring at large expense.

' It will be evident that I make theinterior 1y removed by of the blowercasing much more easily acsheets or plates of secured to the flanges 45of the top andbotflanges at the ends' with suffi'ciently tight gaskets.Where the intended pressure is relatively ,parts are then readilyapplied. Either of section 15 removed, permitting free Y It .will beevident that I save the addi-- required for reliable cast iron coveringof initially upon.

of one set and 41, single operation circumferences o pieces at' the same10c may be calked for the fted outjust sufficiently to clear from-,ing{surface.

cessible than haspreviously been the case, greatly'facllitatmg theplacing of my blower close to a vwall or other objectionable limitavingthus described my invention, what I claimas new and desire to secure byLetters Patent is 1. In adevlce of the character'stated, a centralimpeller casing section, semi-circular end pieces attached thereto and asheet metal covering extending from one semi-circular end piece to theother upon the same side of the blower and means for retaining the partstogether.

2. In a device of the character stated, a central impeller casingsection carrying partial shaft bearings having the journal openingsextending in opposite directions in combination with the side sectionstherefor secured to the central section and complemental shaft capscooperating with the bearing blocks.

3. In a device of the character stated, a central impeller casingsection, top and bottom parts therefor, semi-circular end side sectionssupported by the central section and corresponding in semi-circularcontour to the path of travel of the outside of the impellers, impellersfitting within the casing and a side cover member fitting the contoursof the end side sections and adjoining those upon the same side.

4. Ina device of the character stated, a

central impeller section end, side sections fitting thereto and havingcurved peripheries fitting in contour the paths of travel of the outsideof he impeller-wings used, impellers adapted to be used in the casin andside casing members fitting the curve contours, of the end side sectionsand secured thereto. I

5. In a device of the character stated, a central section having partialshaft bearings thereon, removable top and bottom parts therefor andsemi-cylindrical side sections and means for securing the sectionstogether.

6. In a device of the character stated, central sections provided withside, bottom and top flanges at each end, top and bottom membersprovided with end flanges cooperating with the flanges of the centralsectlon and oppositely facing cylindrical side sections having flangesat each end cooperating with they side flanges of the central section.

7. In a device of the character stated, end members provided withvertically divided bearings, a web connecting adjoining bearing parts,vertically disposed webs supporting the said bearing parts and top,bottom and side members adjoining the ends.

8. In a device of the character stated, a central casing member,semi-circular end side portions secured thereto at opposite ends of thecasing and semi-cylindrical side members secured to the semi-circularends.

9. An impeller casing having separable semi-circular flanged end sidemembers and semi-cylindrical side connecting portions united to theflanges.

v 10. A pair of impellers, shafts therefor, an impeller casingvertically divided longitudinally through the axes of the impellershafts, and means for uniting the parts at the planes of division.

11. In a device of the character stated, centrally and oppositelydisposed side casing members divided alongparallel vertical planes,bearings divided along't-he planes of easing division and verticallydisposed flanged supports for said bearings.

i THOMAS IV. GREEN. Witnesses:

HELEN I. KAUFFMAN, GERTRUDE BADER.

